Breaking trust and betraying formal agreements carries a heavy price, often pushing a person past the point of no return. Zedekiah seals his own fate by completely disregarding his sworn oath and breaking his covenant with Nebuchadnezzar, the King of Babylon [מצודת דוד, ביאור שטיינזלץ].
The primary approach among commentators is that the physical gesture of giving a hand refers back to this initial treaty. It was a gesture of a faithful promise, a handshake meant to reinforce the oath and establish a relationship of peace and goodwill. However, other perspectives suggest this gesture represents something entirely different. It might symbolize Zedekiah joining forces and collaborating with the King of Egypt instead [ביאור שטיינזלץ]. Another angle proposes that it was actually Nebuchadnezzar who reached out his hand, offering a peaceful surrender to spare Zedekiah's life, an offer the king flatly refused. Alternatively, the imagery could describe the final moments of the conflict, where Zedekiah lowered his hands and ceased fighting only after the city had already fallen, yet stubbornly maintained his rebellious stance [מלבי״ם].
Because Zedekiah engages in all these acts of rebellion after initially giving his word, he has no way to escape Nebuchadnezzar's reach [מצודת דוד]. His desperate attempt to flee to Egypt is compared to a vine that has been completely uprooted from its soil, leaving it with absolutely no chance of taking hold or surviving [מלבי״ם].